Low-Loss Commercial Deposition Technology for Thick Ferrites and Ferrite/Insulator Films on Printed Circuit Boards

Integration of RF ferrites on printed circuit boards (PCBs) is highly desired for realizing compact, lightweight and low-cost systems with different RF ferrite components, including inductors, antennas and antenna arrays, etc. However, it has been challenging to integrate ferrites on PCBs. Spin spray deposition can produce fully dense, high crystalline quality, and low-loss RF ferrites at a low temperature at a low cost. However, spin spray technique and facilities are not commercially available. Two major challenges severely limit ferrite integration on PCBs by spin spray deposition: (1) limited ferrite film thickness of <5~10 µm; and (2) limited area of deposition on PCBs. Based on their extensive experience on spin spray deposition facilities, processes, ferrite materials, and RF ferrite devices, the PIs have developed new low-temperature spin spray and linear spray deposition technologies and processes for low-loss, high quality ferrite films and ferrite/insulator multilayers with large thickness >5~10 µm, low loss tangent <5% at >1GHz on PCBs, thus enabling low-temperature ferrite deposition large scale (36”×48”) PCB panels. At the same time, new compact integrated RF ferrite devices, including antennas and inductors have been demonstrated on ferrite coated PCBs. The project team is well positioned for the Phase II efforts.